Any word on the whole DDR4/One DIMM per channel thing? All the specs I can find say that DDR4 only supports one, but most of the X79 motherboards we're seeing seem to have two. Perhaps it's backwards-compatible with DDR3?
I also would love an answer to this. Cause all of these x99 boards have eight slots and honestly I wouldn't mind them being ddr3 based and hopefully backwards compatible with sandy/ivy-e.
More binging on the hope that like AMD chipsets the x99 is back portable with the previous sockets as well as the current and that's what we are seeing.
i doubt they are backwards compatible as they are a completely different pin count (280 vs 288) i think they changed the spec of ddr3 to allow more than one dimm - some xeon motherboards even had 3 dimms per channel
I've also heard this, but I just can't wrap my head around it. I'm guessing something was lost in translation through the rumor mill. DDR4 being limited to a single DIMM per channel would be ridiculous and incredibly restrictive, especially in the server/enterprise markets. I think it's more likely that all the X99 boards we've seen thus far is proof that DDR4 is not limited to a single DIMM per channel.
DDR4 is point-to-point like FB-DIMMs. Going to more than one DIMM per channel requires either registered or load reduced DIMMs from my understanding. Unbuffered memory is limited to 1 DIMM per channel.
Wow, that sounds pretty ridiculous, at least from a price and performance perspective. If that's the case clearly DDR4 has been catered to server/enterprise environments. From my limited understanding of FB-DIMMs, registers have a negative impact on performance, and increase complexity and thus costs per DIMM. Am I reading this wrong? Why would JEDEC chose to go that route for a memory specification intended for wide adoption in consumer systems, where multi-DIMMs per channel has long since become the norm?
It's probably due to pcie lanes not being available for that number of ports while still enabling all the other features. It's a smart decision too, because you have many devices you might hook up that have no need for usb3, like keyboards and mice.
The chipset is limited to 6 native USB 3.0 ports, but like 14 USB 2.0 ports (noting that every used 3.0 port also takes up a 2.0 port). So all those additional 2.0 ports come for free but you need additional PCIe controllers if you want more 3.0 ports.
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SirKnobsworth - Thursday, June 12, 2014 - link
Any word on the whole DDR4/One DIMM per channel thing? All the specs I can find say that DDR4 only supports one, but most of the X79 motherboards we're seeing seem to have two. Perhaps it's backwards-compatible with DDR3?Kraszmyl - Thursday, June 12, 2014 - link
I also would love an answer to this. Cause all of these x99 boards have eight slots and honestly I wouldn't mind them being ddr3 based and hopefully backwards compatible with sandy/ivy-e.Aidic06 - Thursday, June 12, 2014 - link
No backwards compatibility for sandy/ivy-e, its a 2011 socket, but its a 2011-3 socket and they are not compatible.Kraszmyl - Friday, June 13, 2014 - link
More binging on the hope that like AMD chipsets the x99 is back portable with the previous sockets as well as the current and that's what we are seeing.f0d - Friday, June 13, 2014 - link
i doubt they are backwards compatible as they are a completely different pin count (280 vs 288)i think they changed the spec of ddr3 to allow more than one dimm - some xeon motherboards even had 3 dimms per channel
f0d - Friday, June 13, 2014 - link
whoops so many typos"i think they changed the spec of ddr3 to allow more than one dimm - some xeon motherboards even had 3 dimms per channel"
was supposed to be
"i think they changed the spec of DDR4 to allow more than one dimm - some DDR4 xeon motherboards even had 3 dimms per channel"
dragonsqrrl - Friday, June 13, 2014 - link
I've also heard this, but I just can't wrap my head around it. I'm guessing something was lost in translation through the rumor mill. DDR4 being limited to a single DIMM per channel would be ridiculous and incredibly restrictive, especially in the server/enterprise markets. I think it's more likely that all the X99 boards we've seen thus far is proof that DDR4 is not limited to a single DIMM per channel.Kevin G - Tuesday, June 17, 2014 - link
DDR4 is point-to-point like FB-DIMMs. Going to more than one DIMM per channel requires either registered or load reduced DIMMs from my understanding. Unbuffered memory is limited to 1 DIMM per channel.http://www.ti.com.cn/cn/lit/ml/slyt534/slyt534.pdf
dragonsqrrl - Monday, July 21, 2014 - link
Wow, that sounds pretty ridiculous, at least from a price and performance perspective. If that's the case clearly DDR4 has been catered to server/enterprise environments. From my limited understanding of FB-DIMMs, registers have a negative impact on performance, and increase complexity and thus costs per DIMM. Am I reading this wrong? Why would JEDEC chose to go that route for a memory specification intended for wide adoption in consumer systems, where multi-DIMMs per channel has long since become the norm?BreakArms - Thursday, June 12, 2014 - link
USB 2.0 on a Chipset in 2014. Yawn, Intel.RaistlinZ - Thursday, June 12, 2014 - link
I don't get that either. Can't you use USB 2.0 devices in USB 3.0 ports? Why not just make all the ports USB 3.0?Aidic06 - Thursday, June 12, 2014 - link
It's probably due to pcie lanes not being available for that number of ports while still enabling all the other features. It's a smart decision too, because you have many devices you might hook up that have no need for usb3, like keyboards and mice.SirKnobsworth - Thursday, June 12, 2014 - link
The chipset is limited to 6 native USB 3.0 ports, but like 14 USB 2.0 ports (noting that every used 3.0 port also takes up a 2.0 port). So all those additional 2.0 ports come for free but you need additional PCIe controllers if you want more 3.0 ports.djfirestorm - Wednesday, July 16, 2014 - link
Some USB devices WILL NOT WORK PROPERLY on USB 3 host controllers. Yeah Intel for knowing more than the trolls!XZerg - Thursday, June 12, 2014 - link
USB 2.0 to allow Windows 7 installation from Flash - i like that as long as one port only, heck it can even be hybrid usb 2.0/esata.Gigaplex - Friday, June 13, 2014 - link
You'll also need a port for the keyboardUltraWide - Thursday, June 12, 2014 - link
I actually like the "functional" heatsink more than the fancy toys everyone is using these days.Antronman - Friday, June 20, 2014 - link
Just another ugly, not Asus motherboard.